1. Field of the Invention
The present invention relates to a method for producing nano-phase TaC-transition metal based complex powder, and more particularly, to a method for producing nano-sized TaC-transition metal based complex powder for use in a solid carbide cutting tool.
2. Background of the Related Art
TaC is known as a material added to WC—TaC—Co based solid carbide cutting tools to increase high temperature hardness and inhibit reaction with stainless steel to be cut. Also, it is used as a main ingredient of TaC based cermet tools. Recently, it has been found that when ultra fine powders of TaC based carbides are used in a tool, the tool has increased hardness, transverse-rupture strength and wear-resistance. Therefore, TaC based powder as fine as possible is used in production of tools or molds.
According to the conventional methods for producing TaC powder, a powder mixture of Tantalum oxide and carbon is subjected to a thermal treatment at a high temperature of 1500° C. to 1600° C. in a non-oxidizing atmosphere, such as vacuum, inert atmosphere, hydrogen atmosphere, for reduction by carbon and carburization, to prepare TaC powder. However, such methods have disadvantages in that the invested cost of equipments is great and the power consumption is much, since reaction temperature is so high. Also, the produced TaC powder has a coarse particle size of about 1 to 2 μm.